Posts Tagged ‘Miami Beach’

Moving Sand

Friday, September 20th, 2013

Even in a more stable world, undisturbed by the collateral damage of a warming climate, sand beaches and dunes are forever growing, shrinking, changing shape and moving as storms and waves do their familiar work.

For decades the Army Corps of Engineers has defended the sandy coastline from Cape Cod to the southern tip of Florida, dredging or pumping up offshore sand to replenish eroding beaches, and plowing up sand ridges to prevent more wave and surge damage to coastal properties.

Their current efforts in both New Jersey and Florida are much in the news.

The ten miles of Miami Beach have depended on sand replenishment since the 1970s, but nearby sources of offshore sand have now run out. Where will more sand come from? North Carolina? The Bahamas? At what cost? And can there be a Miami Beach without a beach for tourists to frolic on?

Beach replenishment restored a beach front to Miami Beach, but now what? (geology.upm.edu

Beach replenishment restored a beach front to Miami Beach, but now what? (geology.upm.edu

Meanwhile, for years the Army Corps of Engineers has been busy building sand ridges and dunes seaward of beach communities along the New Jersey coast. Where they have been prevented from building by beach-front homeowners, Hurricane Sandy did its most impressive damage. Most people who own such homes now recognize that having a dune blocking their view of the ocean is far better than having their home swept away, and have granted easements to have the remaining dunes built.

The New Jersey shore. Created 'dunes' protect parts of it, but they are only a short-term solution (nj.com)

The New Jersey shore. Created ‘dunes’ protect parts of it, but they are only a short-term solution (nj.com)

The Army Corps of Engineers, here plowing up a ridge on the NJ shore, is charged with the impossible task of defending the coastline against the sea (usatoday.com)

The Army Corps of Engineers, here plowing up a ridge on the NJ shore, is charged with the impossible task of defending the coastline against the sea (usatoday.com)

Not all agree, of course, not wanting to lose their ocean views, and feelings have run high. Since dune protection isn’t much use if there are gaps in the dunes, the State’s Supreme Court has granted communities the ability to take ocean front space by eminent domain where holdouts refuse to grant easements, and the reamining dunes will no doubt soon be built.

Sand ridges plowed up in front of shore front homes will provide only short-term protection (fema.gov).

Sand ridges plowed up in front of shore front homes will provide only short-term protection (fema.gov).

These are of course very short-term solutions. Beach replenishment is so clearly unsustainable, financially costly, and environmentally damaging, while plowing up sand ridges in front of beach-front homes does not make them dunes – they are temporary and unstable mounds of sand. These defenses will fail.

Instead, in the face of rising sea levels and increasingly intense storms, now is the time to initiate long-term responses. New Jersey’s Gov Christie understands this, and no doubt feels constrained by the stubbornness of coastal home owners. Florida’s Gov Rubio apparently does not accept the reality of climate change, so any leadership in Florida must continue to come from the county and municipal level.

Managed retreat is probably the best long-term option. The sand spits and barrier islands along the east coast should become free of human communities, left as sanctuaries and as natural buffers against the sea and climate changes that are occurring. We need their protection, and they need to be free to respond dynamically to the resculpting forces of winds and waves. Where barrier islands do not exist, communities need to retreat inland and to higher ground if it exists.

We can start this soon, with care and organized planning. If we wait, we will still have to do it, but it will be done in the face of catastrophe, the worst of circumstances.

And Miami Beach? Loss of its beaches is not its greatest problem. Miami is the US city most vulnerable to the impact of sea level rise, and it has nowhere to go.